Patch "usb: gadget: f_uac2: fix calculation of uac2->p_interval" has been added to the 4.1-stable tree

Patch "usb: gadget: f_uac2: fix calculation of uac2->p_interval" has been added to the 4.1-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    usb: gadget: f_uac2: fix calculation of uac2->p_interval

to the 4.1-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     usb-gadget-f_uac2-fix-calculation-of-uac2-p_interval.patch
and it can be found in the queue-4.1 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From c41b7767673cb76adeb2b5fde220209f717ea13c Mon Sep 17 00:00:00 2001
From: Peter Chen <peter.chen@freescale.com>
Date: Mon, 27 Jul 2015 14:51:47 +0800
Subject: usb: gadget: f_uac2: fix calculation of uac2->p_interval

From: Peter Chen <peter.chen@freescale.com>

commit c41b7767673cb76adeb2b5fde220209f717ea13c upstream.

The p_interval should be less if the 'bInterval' at the descriptor
is larger, eg, if 'bInterval' is 5 for HS, the p_interval should be
8000 / 16 = 500.

It fixes the patch 9bb87f168931 ("usb: gadget: f_uac2: send
reasonably sized packets")

Fixes: 9bb87f168931 ("usb: gadget: f_uac2: send reasonably sized packets")
Acked-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/usb/gadget/function/f_uac2.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/usb/gadget/function/f_uac2.c
+++ b/drivers/usb/gadget/function/f_uac2.c
@@ -1162,14 +1162,14 @@ afunc_set_alt(struct usb_function *fn, u
 			factor = 1000;
 		} else {
 			ep_desc = &hs_epin_desc;
-			factor = 125;
+			factor = 8000;
 		}
 
 		/* pre-compute some values for iso_complete() */
 		uac2->p_framesize = opts->p_ssize *
 				    num_channels(opts->p_chmask);
 		rate = opts->p_srate * uac2->p_framesize;
-		uac2->p_interval = (1 << (ep_desc->bInterval - 1)) * factor;
+		uac2->p_interval = factor / (1 << (ep_desc->bInterval - 1));
 		uac2->p_pktsize = min_t(unsigned int, rate / uac2->p_interval,
 					prm->max_psize);
 


Patches currently in stable-queue which might be from peter.chen@freescale.com are

queue-4.1/usb-chipidea-ehci_init_driver-is-intended-to-call-one-time.patch
queue-4.1/usb-udc-core-add-device_del-call-to-error-pathway.patch
queue-4.1/usb-gadget-f_uac2-fix-calculation-of-uac2-p_interval.patch